title: Raw potato starch in weaned pig diets and its influence on postweaning scours and the molecular microbial ecology of the digestive tract.
abstract: We evaluated the effect of raw potato starch (RPS) on growth performance, postweaning diarrhea, and gastrointestinal microbial populations in weaned piglets. Eighty-four piglets were weaned at 17 +/- 2 d of age with an average BW of 6.0 +/- 0.9 kg. Pigs were blocked by BW and assigned to 1 of 4 diets in a randomized complete block design with 7 replicate pens per diet and 3 pigs per pen. Treatments were 1) a positive control (PC) containing an antibiotic, 2) a negative control (NC) with no RPS and no antibiotic, 3) NC + 7% RPS (7% RPS), and 4) NC + 14% RPS (14% RPS). Diets were corn-wheat-soybean meal-based and formulated to meet NRC (1998) recommendations. The ADG, ADFI, and G:F ratio were determined weekly. Fecal consistency (FC) scoring was determined daily. After wk 3, 1 pig with a BW closest to the pen mean was killed to evaluate ileal and colonic mucosal-attached Escherichia coli and lactic acid bacteria, as well as digesta pH, VFA, and ammonia N concentrations. The DNA was extracted from ileum and colon digesta and used for molecular microbial evaluations using terminal-RFLP analysis of 16S rDNA genes. The ADG for wk 1 was greater (P < 0.01) for the PC diet, but diet had no effect on ADG during wk 3. The ADFI did not differ among treatments during the first 2 wk, and ADFI was least for 7% RPS diet during wk 3. The NC diet had a greater (P < 0.05) FC score during wk 1 than other treatments, but diet had no effect on FC score during wk 2 and 3. Diets had no effect on the colon lactic acid bacterial counts; however, the PC diet had decreased (P < 0.05) colon E. coli counts than other treatments. Ileum and colon digesta pH and total VFA concentrations did not differ among treatments. Pigs fed with 7 and 14% RPS diets had greater (P < 0.05) ileum ammonia N concentration compared with pigs fed with other diets. There was more diarrhea (P < 0.05) in the 14% than the 7% RPS and control treatments at d 21. This difference correlated with a decline (P < 0.05) in microbial diversity in the colon. We concluded that 7% RPS can be used to prevent postweaning diarrhea in weaned piglets, but there are no effects on growth performance.
authors.affiliation: Department of Animal Science, University of Manitoba, Winnipeg, Manitoba, Canada.
authors.forename: S K
authors.initials: SK
authors.lastname: Bhandari
authors.forename: C M
authors.initials: CM
authors.lastname: Nyachoti
authors.forename: D O
authors.initials: DO
authors.lastname: Krause
mesh_terms: D000821:Animal Feed / Q000032:analysis; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D001419:Bacteria / Q000235:genetics / Q000302:isolation & purification; D018407:Bacterial Physiological Phenomena; D044822:Biodiversity; D001835:Body Weight / Q000502:physiology; D003106:Colon / Q000382:microbiology; D004032:Diet / Q000662:veterinary*; D005766:Gastrointestinal Contents / Q000737:chemistry; D041981:Gastrointestinal Tract / Q000382:microbiology*; D007413:Intestinal Mucosa / Q000382:microbiology; D009929:Organ Size / Q000502:physiology; D012150:Polymorphism, Restriction Fragment Length; D011897:Random Allocation; D011198:Solanum tuberosum / Q000378:metabolism*; D013213:Starch / Q000008:administration & dosage*; D013552:Swine / Q000378:metabolism* / Q000382:microbiology*; D014886:Weaning
chemical_list: D013213:Starch